The present invention relates to spectrometers, and more particularly to a technique for spectrograph calibration.
Spectrometer devices are useful in monitoring for the presence of certain types of chemicals. For example, a spectrometer device may use principles of Raman scattering to analyze a liquid, solid or gas material for certain chemicals. In one type of spectrometer device, a light dispersing element (also referred to as a spectrograph or diffraction grating) is provided to disperse light from a sample and the dispersed light is detected by a detector, such as a charge-coupled camera device. Pixels on the detector are activated depending on the nature of the dispersed light and data representing the spectrum produced by the detector is analyzed to determine the presence of one or more chemicals.
The performance of a spectrometer depends on the mechanical alignment of its components, on temperature and pressure conditions in and around the device, and in particular on the light dispersing element. To ensure accuracy of the measurements and analysis made by a spectrometer, it is necessary to adjust or calibrate for such variations.